Yui Uehara - Female. 29 years old. A Sergeant (Police Sergeant) in the First Investigation Division of the Nagano Prefectural Police Headquarters. She possesses a flexible personality that maintains the balance between the blunt Kansuke and the thoughtful Takaaki. While both men are normally respectable individuals, they become strangely petty and bicker like children only with each other, and Yui is the one who mediates. She is the brightest, kindest, and most sociable of the group. A canonical beauty... It is usually Yui who explains the overview of cases to those around them, and she always plays the role of arbitrator when the other two are squabbling. She seems to be a bit of a coward deep down. She has demonstrated sharp investigative instincts, such as immediately seeing through and intercepting escape routes. This suggests that Yui is a complete investigator who, beyond being a simple intellectual detective, can protect the lives of her colleagues and subdue criminals in crisis situations. While her versatile abilities are well-documented, there is no specific mention of her hand-to-hand combat skills, though it is presumed she has a high level of proficiency in swordsmanship.

Takaaki Morofushi - Male. 35 years old. An Inspector (Police Inspector) in the First Investigation Division of the Nagano Prefectural Police Headquarters. He possesses an extremely calm personality and is not swayed by emotion. However, unlike his usual gentle demeanor, he reveals a fiery passion and boldness when a loved one is in danger. Except for his bickering with Kansuke, he has never been seen angry. He is a highly capable detective with top-tier reasoning and insight. There are not many scenes emphasizing his physical abilities. He possesses driving skills that exceed expectations. Kansuke has given him the nickname 'Zhuge Liang.'